[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[PULL 31/53] KVM: x86: believe what KVM says about WAITPKG
From: |
Paolo Bonzini |
Subject: |
[PULL 31/53] KVM: x86: believe what KVM says about WAITPKG |
Date: |
Mon, 6 Jul 2020 12:41:33 -0400 |
Currently, QEMU is overriding KVM_GET_SUPPORTED_CPUID's answer for
the WAITPKG bit depending on the "-overcommit cpu-pm" setting. This is a
bad idea because it does not even check if the host supports it, but it
can be done in x86_cpu_realizefn just like we do for the MONITOR bit.
This patch moves it there, while making it conditional on host
support for the related UMWAIT MSR.
Cc: qemu-stable@nongnu.org
Reported-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
target/i386/cpu.c | 3 +++
target/i386/kvm.c | 11 +++++------
target/i386/kvm_i386.h | 1 +
3 files changed, 9 insertions(+), 6 deletions(-)
diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index c44cc510e1..dc9ba06f1f 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -6536,6 +6536,9 @@ static void x86_cpu_realizefn(DeviceState *dev, Error
**errp)
host_cpuid(5, 0, &cpu->mwait.eax, &cpu->mwait.ebx,
&cpu->mwait.ecx, &cpu->mwait.edx);
env->features[FEAT_1_ECX] |= CPUID_EXT_MONITOR;
+ if (kvm_enabled() && kvm_has_waitpkg()) {
+ env->features[FEAT_7_0_ECX] |= CPUID_7_0_ECX_WAITPKG;
+ }
}
if (kvm_enabled() && cpu->ucode_rev == 0) {
cpu->ucode_rev = kvm_arch_get_supported_msr_feature(kvm_state,
diff --git a/target/i386/kvm.c b/target/i386/kvm.c
index 2b6b7443d2..b8455c89ed 100644
--- a/target/i386/kvm.c
+++ b/target/i386/kvm.c
@@ -411,12 +411,6 @@ uint32_t kvm_arch_get_supported_cpuid(KVMState *s,
uint32_t function,
if (host_tsx_blacklisted()) {
ret &= ~(CPUID_7_0_EBX_RTM | CPUID_7_0_EBX_HLE);
}
- } else if (function == 7 && index == 0 && reg == R_ECX) {
- if (enable_cpu_pm) {
- ret |= CPUID_7_0_ECX_WAITPKG;
- } else {
- ret &= ~CPUID_7_0_ECX_WAITPKG;
- }
} else if (function == 7 && index == 0 && reg == R_EDX) {
/*
* Linux v4.17-v4.20 incorrectly return ARCH_CAPABILITIES on SVM hosts.
@@ -4730,3 +4724,8 @@ int kvm_arch_msi_data_to_gsi(uint32_t data)
{
abort();
}
+
+bool kvm_has_waitpkg(void)
+{
+ return has_msr_umwait;
+}
diff --git a/target/i386/kvm_i386.h b/target/i386/kvm_i386.h
index 00bde7acaf..064b8798a2 100644
--- a/target/i386/kvm_i386.h
+++ b/target/i386/kvm_i386.h
@@ -44,6 +44,7 @@ void kvm_put_apicbase(X86CPU *cpu, uint64_t value);
bool kvm_enable_x2apic(void);
bool kvm_has_x2apic_api(void);
+bool kvm_has_waitpkg(void);
bool kvm_hv_vpindex_settable(void);
--
2.26.2
- [PULL 18/53] i386: hvf: Clean up synchronize functions, (continued)
- [PULL 18/53] i386: hvf: Clean up synchronize functions, Paolo Bonzini, 2020/07/06
- [PULL 21/53] MAINTAINERS: Add an 'overall' entry for accelerators, Paolo Bonzini, 2020/07/06
- [PULL 22/53] MAINTAINERS: Cover the HAX accelerator stub, Paolo Bonzini, 2020/07/06
- [PULL 23/53] Makefile: Remove dangerous EOL trailing backslash, Paolo Bonzini, 2020/07/06
- [PULL 24/53] Makefile: Write MINIKCONF variables as one entry per line, Paolo Bonzini, 2020/07/06
- [PULL 16/53] i386: hvf: Move Guest LMA reset to macvm_set_cr0(), Paolo Bonzini, 2020/07/06
- [PULL 25/53] accel/Kconfig: Extract accel selectors into their own config, Paolo Bonzini, 2020/07/06
- [PULL 01/53] tcg/svm: use host cr4 during NPT page table walk, Paolo Bonzini, 2020/07/06
- [PULL 19/53] MAINTAINERS: Add Cameron as HVF co-maintainer, Paolo Bonzini, 2020/07/06
- [PULL 11/53] coverity: provide Coverity-friendly MIN_CONST and MAX_CONST, Paolo Bonzini, 2020/07/06
- [PULL 31/53] KVM: x86: believe what KVM says about WAITPKG,
Paolo Bonzini <=
- [PULL 13/53] i386: hvf: Move synchronize functions to sysemu, Paolo Bonzini, 2020/07/06
- [PULL 15/53] i386: hvf: Make long mode enter and exit clearer, Paolo Bonzini, 2020/07/06
- [PULL 30/53] target/i386: implement undocumented "smsw r32" behavior, Paolo Bonzini, 2020/07/06
- [PULL 20/53] MAINTAINERS: Fix KVM path expansion glob, Paolo Bonzini, 2020/07/06
- [PULL 32/53] target/i386: sev: provide proper error reporting for query-sev-capabilities, Paolo Bonzini, 2020/07/06
- [PULL 26/53] accel/Kconfig: Add the TCG selector, Paolo Bonzini, 2020/07/06
- [PULL 40/53] pc: fix leak in pc_system_flash_cleanup_unused, Paolo Bonzini, 2020/07/06
- [PULL 29/53] target/i386: remove gen_io_end, Paolo Bonzini, 2020/07/06